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The first 25 slides, exactly as they appear. The full deck has 110 content slides.
Anaesthesiology
Invasive monitoring
Built from Al-Shaikh — Essentials of Equipment in Anaesthesia, Critical Care and Peri-operative Medicine, 6e
What’s inside
12 sections · 110 slides
Overview
- What this deck will teach you
Invasive arterial pressure
Reading blood pressure directly from inside an artery
- Why go inside the artery at all
- The parts of the measuring system
- Arterial cannula with an on-off valve
- Arterial cannula with introducer and guidewire
- Components of the pressure-measuring system
- How the transducer senses pressure
- Integrated pressure transducer with flush device
- Mechanism of action, step by step
- The Wheatstone bridge: how tiny changes are read
- The Wheatstone bridge circuit
- Where the cannula goes, and what it tells us
The arterial waveform
Reading the shape, and why the system must be fast enough
- The arterial pressure waveform
- A pulse is really many waves added together
- Reading the shape of the trace
- Getting numbers from the waveform
- Natural frequency: don't let the system sing along
- What sets the natural frequency
Damping, resonance and safety
Recognising a lying trace, and the risks of an arterial line
- Optimally, under- and over-damped waveforms
- Damping: when the trace goes flat and lazy
- Resonance: when the trace overshoots
- The square-wave (fast-flush) test
- The square-wave (fast-flush) test
- Zeroing, levelling and calibration
- Calibrating the invasive pressure monitor
- Risks of an arterial line, part 1
- Risks of an arterial line, part 2
- Invasive arterial pressure: the numbers to know
Central venous access and CVP
Reaching the great veins, and reading the filling pressure of the heart
- What central venous pressure means
- The routes in, and their trade-offs
- The Seldinger technique
- The Seldinger technique, step by step
- Two golden safety rules of insertion
- Ultrasound view of needle in the jugular vein
- Why ultrasound guidance is now routine
- Two ways to read the CVP
- Measuring CVP with a water manometer
- The fluid manometer in detail
The family of central catheters
Lumens, coatings, and lines built for different jobs
- Cannula-over-needle central line
- How catheters differ, and antimicrobial coatings
- Chlorhexidine-impregnated triple-lumen line
- Single, double and triple catheter lumens
- Multilumen catheters
- Adult triple-lumen central catheter
- Paediatric triple-lumen catheter
- Peripherally inserted central catheters (PICCs)
- Double-lumen PICC line
- Hickman (tunnelled) catheters
- Double-lumen tunnelled Hickman catheter
- Final position of a tunnelled Hickman line
- Dialysis catheters
- Complications of central lines
- Cutting central-line infection (CDC bundle)
- Microshock: a hidden electrical danger
Invasive ECG
Reading the heart's electricity from inside the body
- Invasive ECG electrode positions
- Three invasive ways to record the ECG
Measuring cardiac output
Moving from pressure to flow, and the many ways to gauge it
- A short history of cardiac-output monitoring
- The main families of cardiac-output methods
The pulmonary artery catheter
Floating a balloon-tipped catheter through the right heart
- Balloon-tipped flow-guided PA catheter
- What the PA catheter is for
- The lumens of a PA catheter
- PA catheter tip wedged in a branch
- Floating it in, watching the waveform change
- Waveforms as the catheter advances
- Pressure waveforms during PA catheter insertion
- Wedging and measuring cardiac output
- Cardiac output monitor and continuous displays
- Continuous output and mixed venous oximetry
- Fibreoptic mixed-venous oximetry mechanism
- Fibreoptic PA catheter tip
- What a PA catheter can tell you
- Complications of the PA catheter
- When wedge pressure lies about the left heart
Less-invasive flow monitors
Oesophageal Doppler and arterial-waveform cardiac output
- Oesophageal Doppler: the appeal
- Oesophageal Doppler machine and probe
- The Doppler principle behind it
- Placing the probe and reading it
- Oesophageal Doppler waveform changes
- Oesophageal Doppler: limits
- LiDCOrapid: cardiac output from the arterial line
- LiDCOrapid cardiac output monitor
- Where LiDCOrapid struggles, and calibration
Temperature monitoring
Thermistors, thermocouples, and which site tells the truth
- The thermistor
- A thermocouple temperature sensor
- The thermocouple
- The infrared tympanic thermometer
- Which site gives the true core temperature
- Oesophageal or rectal temperature probe
- Tympanic membrane temperature probe
- Infrared tympanic thermometer
- Bladder catheter with temperature probe
- Skin temperature probe
Wrap-up
Key ideas, a viva and the sources
- The three things invasive monitoring measures
- Take-home messages
- Source key-points marker
- How would you check that an invasive arterial trace is telling the truth?
- References
- Essentials of Equipment in Anaesthesia, Critical Care, and Perioperative Medicine